[Letux-kernel] [PATCH v5 5/7] MIPS: DTS: jz4780: Account for Synopsys HDMI driver and LCD controllers

H. Nikolaus Schaller hns at goldelico.com
Tue Nov 9 21:19:17 CET 2021

Hi Paul,

> Am 07.11.2021 um 20:05 schrieb Paul Cercueil <paul at crapouillou.net>:
>> 6. Therefore I think it *may* work overclocked with 48MHz
>> but is not guaranteed or reliable above 27 MHz.
>> So everything is ok here.
> One thing though - the "assigned-clocks" and "assigned-clock-rates", while it works here, should be moved to the CGU node, to respect the YAML schemas.

Trying to do this seems to break boot.

I can boot up to 

[    8.312926] dw-hdmi-ingenic 10180000.hdmi: registered DesignWare HDMI I2C bus driver


[   11.366899] [drm] Initialized ingenic-drm 1.1.0 20200716 for 13050000.lcdc0 on minor 0

but then the boot process becomes slow and hangs. Last sign of activity is

[   19.347659] hub 1-0:1.0: USB hub found
[   19.353478] hub 1-0:1.0: 1 port detected
[   32.321760] wlan0_power: disabling

What I did was to just move

		assigned-clocks = <&cgu JZ4780_CLK_HDMI>;
		assigned-clock-rates = <27000000>;


	hdmi: hdmi at 10180000 {


	cgu: jz4780-cgu at 10000000 {

Does this mean the clock is assigned too early or too late?

Do you have any suggestions since I don't know the details of CGU.

BR and thanks,

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